Gwyneth Paltrow looked youthful and radiant at the signing of her latest cookbook in Los Angeles on Wednesday.

Gwyneth, 40, celebrated the release of her gluten-free recipe book, It's All Good: Delicious, Easy Recipes that will Make You Look Good and Feel Great in Barnes and Noble at The Grove in Los Angeles.

If her glowing complexion, slender figure, lovely blonde locks and long, lean pins are anything to go by, the beauty's latest cookbook is definitely one for the kitchen.

The Oscar-winning actress was the picture of perfection in a demure black and white long-sleeved mini dress by Isabel Marant, showing off her slender figure with a belt nipped in at the waist. Her lovely long limbs were also on display with open-toed black heels by Michael Kors.

Chris Martin showed up to support his stunning wife at the book signing. Although rarely spotted together, the Coldplay frontman was seen taking the couple's two children Apple, eight, and Moses, six, through the back door of the LA bookshop.

After the event, the bookshop thanked Gwyneth on social media network Facebook: "A sincere thank you to Gwyneth Paltrow and all her fans for a fun signing. It's All Good!!!"

Her second publication, this cuisine tome concentrates on gluten-free recipes following a health scare suffered by Gwyneth herself.

"One sunny afternoon in London, in the spring of 2011, I thought – without sounding overly-dramatic – that I was going to die," the Iron Man beauty writes. "I had just served lunch in the garden at home… I had a vague feeing that I was going to faint, and I wasn't forming thoughts correctly.

"I got a searing pain in my head, I couldn't speak, and I felt as if I couldn't breathe, I thought I was having a stroke."

Doctors diagnosed that Gwyneth had suffered from a migraine and a panic attack – and also found that she was severely anaemic and vitamin D-deficient. She was banned from eating eggs, sugar, shellfish, deepwater fish, potatoes, tomatoes, bell peppers, eggplant, corn, wheat, meat and drinking coffee for three weeks.

The American actress then decided to put the fun back into food by compiling a collection of recipes that adhered to her new diet guidelines. And she certainly has, with recipes such as huevos rancheros, hummus tartine with scallion-mint pesto, salmon burgers with pickled ginger, and even chocolate brownies with banana ice cream.

The star, whose book has just hit the shelves, will be making the rounds in America with her new publication. She has another signing in Beverly Hills on April 5, followed by the Big Apple on April 9.

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